U.S. patent application number 12/953568 was filed with the patent office on 2012-05-24 for imaging-based radio-frequency identification transponder.
Invention is credited to Moon J. Kim, Bonwoong Koo.
Application Number | 20120127289 12/953568 |
Document ID | / |
Family ID | 46064011 |
Filed Date | 2012-05-24 |
United States Patent
Application |
20120127289 |
Kind Code |
A1 |
Kim; Moon J. ; et
al. |
May 24, 2012 |
IMAGING-BASED RADIO-FREQUENCY IDENTIFICATION TRANSPONDER
Abstract
The present invention relates to an imaging-based
radio-frequency identification (RFID) transponder. Specifically,
the transponder includes a photo-responsive cell for capturing an
image; and an analysis component. The photo-responsive cell
captures images of objects. Once captured, the analysis component
is configured to: determine whether the RFID transponder has
sufficient power to analyze the image; analyze the image on the
RFID transponder if sufficient power exists; and/or transmit data
corresponding to the image to an RFID reader for analysis in the
event the RFID transponder has insufficient power to analyze the
image. Where quality of the image and/or performance of the
transponder are less than desirous, any number of corrective
approaches can be taken. For example, the setup of the transponder
can be adjusted, the range readout can be reduced, the integration
time per pixel of the image can be increased, etc. Moreover, the
range of the RFID transponder can be increased using any of the
approaches discussed in the above-incorporated patent
applications.
Inventors: |
Kim; Moon J.; (Wappingers
Falls, NY) ; Koo; Bonwoong; (Los Altos, CA) |
Family ID: |
46064011 |
Appl. No.: |
12/953568 |
Filed: |
November 24, 2010 |
Current U.S.
Class: |
348/61 ;
348/E7.085 |
Current CPC
Class: |
H04N 7/183 20130101 |
Class at
Publication: |
348/61 ;
348/E07.085 |
International
Class: |
H04N 7/18 20060101
H04N007/18 |
Claims
1. An imaging-based radio-frequency identification (RFID)
transponder, comprising: a photo-responsive cell for capturing an
image; and an analysis component for analyzing the image on the
RFID transponder based on an available power in the RFID
transponder.
2. The imaging-based RFID transponder of claim 1, further
comprising a light source for improving a quality of the image when
captured by the photo-responsive cell.
3. The imaging-based RFID transponder of claim 1, the analysis
component being further configured to transmit data corresponding
to the image to an RFID reader for analysis in the event the RFID
transponder has insufficient power to analyze the image.
4. The imaging-based RFID transponder of claim 1, the RFID reader
being configured to adjust a quality with which the RFID
transponder operates.
5. The imaging-based RFID transponder of claim 4, the quality being
adjusted by adjusting a setup of the RFID transponder.
6. The imaging-based RFID transponder of claim 4, the quality being
adjusted by reducing a readout range of the RFID transponder.
7. The imaging-based RFID transponder of claim 4, the quality being
adjusted by increasing an integration time per pixel of the
image.
8. An imaging-based radio-frequency identification (RFID)
transponder, comprising: a photo-responsive cell for capturing an
image; and an analysis component being configured to: determine
whether the RFID transponder has sufficient power to analyze the
image; analyze the image on the RFID transponder if sufficient
power exists; and transmit data corresponding to the image to an
RFID reader for analysis in the event the RFID transponder has
insufficient power to analyze the image.
9. The imaging-based RFID transponder of claim 8, further
comprising a light source for improving a quality of the image when
captured by the photo-responsive cell.
10. The imaging-based RFID transponder of claim 8, the RFID reader
being configured to adjust a quality with which the RFID
transponder operates.
11. The imaging-based RFID transponder of claim 10, the quality
being adjusted by adjusting a setup of the RFID transponder.
12. The imaging-based RFID transponder of claim 10, the quality
being adjusted by reducing a readout range of the RFID
transponder.
13. The imaging-based RFID transponder of claim 10, the quality
being adjusted by increasing an integration time per pixel of the
image.
14. A method for capturing an image using a radio-frequency
identification (RFID) transponder, comprising: capturing an image
using a photo-responsive cell integrated with the RFID transponder;
determining whether the RFID transponder has sufficient power to
analyze the image; analyzing the image on the RFID transponder if
sufficient power exists; and transmitting data corresponding to the
image to an RFID reader for analysis if the RFID transponder has
insufficient power to analyze the image.
15. The method of claim 14, the determining comprising comparing a
current power level of the RFID transponder to a predetermined
threshold, the predetermined threshold being a minimum amount of
power needed to analyze the image on the RFID transponder.
16. The method of claim 14, further comprising illuminating an
object from which the image is taken using a light source
integrated with the RFID transponder.
17. The method of claim 14, further comprising adjusting a quality
with which the RFID transponder operates using the RFID reader.
18. The method of claim 17, the adjusting comprising adjusting a
setup of the RFID transponder.
19. The method of claim 17, the adjusting comprising reducing a
readout range of the RFID transponder.
20. The method of claim 17, the adjusting comprising increasing an
integration time per pixel of the image.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related in some aspects to co-pending
application Ser. No. 12/949,033, entitled "STRONG PASSIVE AD-HOC
RADIO-FREQUENCY IDENTIFICATION (RFID)", which was filed on Nov. 18,
2010, the entire contents of which are herein incorporated by
reference. This application is also related in some aspects to
co-pending application Ser. No. 12/950,188, entitled "ACTIVE ENERGY
HARVESTING FOR RADIO-FREQUENCY IDENTIFICATION DEVICES", which was
filed on Nov. 19, 2010, the entire contents of which are herein
incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to radio-frequency
identification (RFID) technology. Specifically, the present
invention relates to an imaging-based RFID transponder.
BACKGROUND OF THE INVENTION
[0003] Over recent years, RFID has become an increasing function of
providing wireless communications. For example, RFID is commonly
implemented in security devices (e.g., swipers and/or card readers)
for businesses as well as in many other areas. Unfortunately, RFID
is typically passive and has its range limited by distance and
physical obstacles. Moreover, RFID reader power is limited by
regulation, which causes range issues since RFID operational range
is constrained by the available power. As such, RFID reliability,
responsiveness, and functionality are commonly compromised in
practical environments. The related art has failed to provide such
functionality, including those references listed below:
[0004] U.S. Pat. No. 7,786,868 discloses an RFID device with
multiple passive operation modes that are fully passive or boosted
passive. The boosted passive mode utilizes an internal energy
booster. The energy booster may include a one-port transistor and
an energy source that is used to power the transistor.
[0005] U.S. Pat. No. 7,443,299 discloses an extended range RFID
system for discs such as CDs, DVDs, or minidiscs. A special RFID
transponder and antenna configuration is used and antenna elements
are coupled to the transponder extending in opposite directions
across an outer annular zone. The monopole or dipole mode of
antenna operation (utilizing a metalized disc layer) results from
this antenna configuration and is stated as "to more than double
the range of the system".
[0006] U.S. Pat. No. 7,374,105 discloses an RFID tag having an RFID
integrated circuit and an antenna that are combined with a first
passive antenna circuit to provide an extended operating range. The
second passive antenna circuit is essentially identical to the
first antenna, only it has larger dimensions, and is positioned
with the coil of the second passive antenna circuit surrounding the
first coil to extend the operating range.
[0007] U.S. Patent Application 20090289773 discloses a method for
extending the read range of passive RFID tags. Excess excitation
energy is dissipated through circuitry for a constant current power
supply that is implemented either with discrete components
integrated into the ASIC design, a network that minimizes the
amount of energy that is converted to heat by a traditional
configuration's shunt regulator, and/or a sleep mode for reducing
the energy consumed by an RFID tag after it has been read.
[0008] U.S. Patent Application 20090085750 discloses an extended
RFID tag. The extended range RFID tag includes a UHF RFID tag
having a dipole antenna attached to a surface of a substrate and
further includes an antenna extension that overlaps a portion of
the dipole antenna for electromagnetically coupling the antenna
extension and the dipole antenna when in operation.
[0009] U.S. Patent Application 20070285244 discloses a long-range
RFID transponder. The improved range is achieved through the RFID
power generation's Passive Magnetostrictive Electroactive device
component. One example includes a passive magnetic field sensor
made of layers of Terfenol-D magnetostrictive material and ceramic
PXT-5 to act as a generator to power the RFID when in range of the
querying transceiver magnetic field.
[0010] U.S. Pat. No. 7,659,821 discloses a smart RFID
infrastructure and method that enables communication between RFID
tags. Information tables from individual RFID tags are aggregated
into master information tables on writeable RFID tags.
[0011] U.S. Pat. No. 7,515,049 discloses an extended read range
RFID system. This system utilizes an apparatus to extend the
reader's antenna signal to a location proximate to the RFID tag. In
another embodiment, the apparatus utilizes at least one magnetic
rod to create a magnetic path for the RF field to travel between
the reader's antenna and the RFID tag.
[0012] U.S. Patent Application 20100201488 discloses a system for
displaying read range of an RFID reader based upon feedback from
fixed RFID beacon tags. An interrogation signal is transmitted from
the RFID reader to these fixed RFID beacon tags at known
locations.
[0013] U.S. Patent Application 20060202032 discloses an automatic
identification and data capture system.
SUMMARY OF THE INVENTION
[0014] In general, the present invention relates to an
imaging-based radio-frequency identification (RFID) transponder.
Specifically, the transponder includes a photo-responsive cell for
capturing an image; and an analysis component. The photo-responsive
cell captures images of objects. Once captured, the analysis
component is configured to: determine whether the RFID transponder
has sufficient power to analyze the image; analyze the image on the
RFID transponder if sufficient power exists; and/or transmit data
corresponding to the image to an RFID reader for analysis in the
event the RFID transponder has insufficient power to analyze the
image. Where quality of the image and/or performance of the
transponder are less than desirous, any number of corrective
approaches can be taken. For example, the setup of the transponder
can be adjusted, the range readout can be reduced, the integration
time per pixel of the image can be increased, etc. Moreover, the
range of the RFID transponder can be increased using any of the
approaches discussed in the above-incorporated patent
applications.
[0015] A first aspect of the present invention provides an
imaging-based radio-frequency identification (RFID) transponder,
comprising: a photo-responsive cell for capturing an image; and an
analysis component for analyzing the image on the RFID transponder
based on an available power in the RFID transponder.
[0016] A second aspect of the present invention provides an
imaging-based radio-frequency identification (RFID) transponder,
comprising: a photo-responsive cell for capturing an image; and an
analysis component being configured to: determine whether the RFID
transponder has sufficient power to analyze the image; analyze the
image on the RFID transponder if sufficient power exists; and
transmit data corresponding to the image to an RFID reader for
analysis in the event the RFID transponder has insufficient power
to analyze the image.
[0017] A third aspect of the present invention provides an method
for capturing an image using a radio-frequency identification
(RFID) transponder, comprising: capturing an image using a
photo-responsive cell integrated with the RFID transponder;
determining whether the RFID transponder has sufficient power to
analyze the image; analyzing the image on the RFID transponder if
sufficient power exists; and transmitting data corresponding to the
image to an RFID reader for analysis if the RFID transponder has
insufficient power to analyze the image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] These and other features of this invention will be more
readily understood from the following detailed description of the
various aspects of the invention taken in conjunction with the
accompanying drawings in which:
[0019] FIG. 1 depicts an RFID configuration according to an
embodiment of the present invention.
[0020] FIG. 2 depicts an imaging-based RFID transponder according
to an embodiment of the present invention.
[0021] FIGS. 3A-B depict image analysis/processing components
according to an embodiment of the present invention.
[0022] FIGS. 4A-B show photon behavior according to an embodiment
of the present invention.
[0023] FIG. 5 shows image organization according to an embodiment
of the present invention.
[0024] FIG. 6 shows a method flow diagram for analyzing an image
according to an embodiment of the present invention.
[0025] FIGS. 7A-B show the impact of quality and environment on
readout block size according to an embodiment of the present
invention.
[0026] FIG. 8 depicts a method flow diagram for adjusting a setup
of an RFID to improve image quality according to an embodiment of
the present invention.
[0027] FIG. 9 depicts a method flow diagram for reducing range
readout to improve image quality according to an embodiment of the
present invention.
[0028] FIG. 10 depicts a method flow diagram for increasing
integration time per pixel to improve image quality according to an
embodiment of the present invention.
[0029] The drawings are not necessarily to scale. The drawings are
merely schematic representations, not intended to portray specific
parameters of the invention. The drawings are intended to depict
only typical embodiments of the invention, and therefore should not
be considered as limiting the scope of the invention. In the
drawings, like numbering represents like elements.
DETAILED DESCRIPTION OF THE INVENTION
[0030] For convenience, the Detailed Description of the Invention
has the following sections: [0031] I. General Description of the
Invention [0032] II. Illustrative Implementation
I. General Description of the Invention
[0033] Illustrative embodiments will now be described more fully
herein with reference to the accompanying drawings, in which
exemplary embodiments are shown. This disclosure may, however, be
embodied in many different forms and should not be construed as
limited to the exemplary embodiments set forth herein. Rather,
these exemplary embodiments are provided so that this disclosure
will be thorough and complete and will fully convey the scope of
this disclosure to those skilled in the art. In the description,
details of well-known features and techniques may be omitted to
avoid unnecessarily obscuring the presented embodiments.
[0034] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
this disclosure. As used herein, the singular forms "a", "an", and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. Furthermore, the use of the
terms "a", "an", etc., do not denote a limitation of quantity, but
rather denote the presence of at least one of the referenced items.
It will be further understood that the terms "comprises" and/or
"comprising", or "includes" and/or "including", when used in this
specification, specify the presence of stated features, regions,
integers, steps, operations, elements, and/or components, but do
not preclude the presence or addition of one or more other
features, regions, integers, steps, operations, elements,
components, and/or groups thereof.
[0035] In general, RFID is a technology that incorporates the use
of electromagnetic or electrostatic coupling in the radio frequency
(RF) portion of the electromagnetic spectrum to uniquely identify
an object, animal, or person. RFID is coming into increasing use in
the industry as an alternative to the bar code. The advantage of
RFID is that it does not require direct contact or line-of-sight
scanning. An RFID system consists of three components: an antenna
and transceiver (often combined into one reader) and a transponder
(the tag). The antenna uses radio frequency waves to transmit a
signal that activates the transponder. When activated, the tag
transmits data back to the antenna. The data is used to notify a
programmable logic controller that an action should occur. The
action could be as simple as raising an access gate or as
complicated as interfacing with a database to carry out a monetary
transaction. Low-frequency RFID systems (e.g., 30 KHz to 500 KHz)
have short transmission ranges (generally less than six feet).
High-frequency RFID systems (850 MHz to 950 MHz and 2.4 GHz to 2.5
GHz) offer longer transmission ranges (more than 90 feet). RFID is
sometimes called dedicated short range communication (DSRC).
[0036] RFID tags and labels (collectively referred to herein as
"devices" or "transponders") are widely used to associate an object
with an identification code or other information. RFID devices
generally have a combination of antennas and analog and/or digital
electronics, which may include, for example, communications
electronics, data memory, and control logic. For example, RFID tags
are used in conjunction with security locks in cars, for access
control to buildings, and for tracking inventory and parcels. As
noted above, RFID devices are generally categorized as labels or
tags. RFID labels are RFID devices that are adhesive or otherwise
have a surface attached directly to objects. RFID tags, in
contrast, are secured to objects by other means (for example, by
use of a plastic fastener, string, or other fastening means).
[0037] RFID devices include: (1) active tags and labels, which
include a power source for broadcasting signals; and (2) passive
tags and labels, which do not. In the case of passive devices, in
order to retrieve the information from the chip, a "base station"
or "reader" sends an excitation signal to the RFID tag or label.
The excitation signal energizes the tag or label, and the RFID
circuitry transmits the stored information back to the reader. The
RFID reader receives and decodes the information from the RFID tag.
In general, RFID tags can retain and communicate enough information
to uniquely identify individuals, packages, inventory, and the
like. RFID tags and labels also can be characterized as those to
which information is written only once (although the information
may be read repeatedly), and those to which information may be
written to repeatedly during use. For example, RFID tags may store
environmental data (that may be detected by an associated sensor),
logistical histories, state data, etc.
[0038] Along these lines, RFID devices can be further characterized
as passive, semi-passive, and active RFID devices. Passive RFID
devices have no internal power supply. Power for operation of
passive RFID devices is provided by the energy in an incoming radio
frequency signal received by the device. Most passive RFID devices
signal by backscattering the carrier wave from an RF reader.
Passive RFID devices have the advantage of simplicity and long
life, although performance of them may be limited.
[0039] As indicated above, the present invention relates to an
imaging-based radio-frequency identification (RFID) transponder.
Specifically, the transponder includes a photo-responsive cell for
capturing an image; and an analysis component. The photo-responsive
cell captures images of objects. Once captured, the analysis
component is configured to: determine whether the RFID transponder
has sufficient power to analyze the image; analyze the image on the
RFID transponder if sufficient power exists; and/or transmit data
corresponding to the image to an RFID reader for analysis in the
event the RFID transponder has insufficient power to analyze the
image. Where quality of the image and/or performance of the
transponder are less than desirous, any number of corrective
approaches can be taken. For example, the setup of the transponder
can be adjusted, the range readout can be reduced, the integration
time per pixel of the image can be increased, etc. Moreover, the
range of the RFID transponder can be increased using any of the
approaches discussed in the above-incorporated patent
applications.
[0040] Referring now to FIG. 1, an illustrative RFID configuration
according to the present invention is shown. As depicted,
configuration 10 shows an RFID transceiver/reader 12 communicating
with RFID transponder 14. Transponder 14 can be any type of RFID
transponder now known or later developed. Examples include the
aforementioned labels and/or tags. As further shown, RFID reader 12
and RFID transponder 14 will exchange data (e.g., security
information, etc.). Under the present invention, these types of
components will be leveraged to create a strong passive ad-hoc RFID
network that is (among other things) capable of communicating over
longer distances and around physical objects.
[0041] Under the present invention, a transponder such as
transponder 14 will be adapted to incorporate image capture and
analysis functionality. Referring now to FIG. 2, an RFID
transponder 20 having a photo-responsive cell and an optional light
source 24 is shown. In general, it includes various components that
allow: an image to be captured; a determination to be made whether
sufficient power exists in the RFID transponder to analyze the
image; analyze/process the image if sufficient power exists;
transfer data corresponding to the image to an RFID reader if
insufficient power exists; and/or employ various approaches for
improving image quality.
[0042] FIGS. 3A-B show components that can be incorporated within
the transponder 20 of FIG. 2. As depicted, transponder 20 can
include a controller 30, which can control photo-responsive cell 22
of FIG. 2 to capture an image using optional light source 24 for
illumination. When an image is captured, an area to be mapped to
pixel 36 is designated. Then, a light detection pixel 34 and an
analog-to-digital converter 32 will be utilized to process/analyze
the image. Along these lines, controller 30 can determine whether
transponder 20 has sufficient power to perform a
processing/analysis 38. If not, the image (or image data) can be
transferred to an RFID reader in communication with transponder 20
to perform any such processing/analysis. If, however, sufficient
power does exist, then processing/analysis component 38 can perform
the same. As shown in FIG. 3B, pixels 38A-N are fed to
analog-to-digital converter 32 so that the image will be in digital
format when processed/analyzed. Along these lines, image read out
data can be based upon any of the following characteristics:
pixel-by-pixel or partial readout depending on power, illumination,
sensitivity, number of intensity levels, decision threshold,
channel condition, etc.
[0043] FIGS. 4A-B show one possible embodiment of photo-responsive
cell 22 of FIG. 2 and its interaction with photon 56. As depicted,
in FIG. 4A, a depletion region 54 can be provided between an N-type
region 50 and a P-type region 52. As shown, a photon 56 will impact
the hole/electric pair in depletion region 54. As shown in FIG. 4B,
any type of photo-sensitive cell can be implemented hereunder. One
such example is a photo PN diode 58 which can be impacted by photon
56. FIG. 5 shows how image data can be organized and/or processed
hereunder. As depicted, image data can be implemented in a
column-row matrix 60. Based thereon, a column readout 62 can be
made and fed to a data converter 64 for processing.
II. Illustrative Embodiment
[0044] Referring now to FIG. 6, an illustrative flow diagram of an
image capture and analysis method based on the concepts of FIGS.
1-5. As shown, in step K1, power is activated and in step K2, the
optional light can be activated. In step K3, the image is captured.
In step K4, it is determined whether there is sufficient power to
analyze/process the image on the transponder. If so, the image is
processed in step K5, and transmitted to the RFID reader in step
K6. If sufficient power was not present, the image data will be
transmitted to the RFID reader in step K7 where it will be
processed/analyzed. Regardless, the process can then terminate in
step K8.
[0045] Once the image has been captured, image quality, processing,
etc., can be affected by various elements. For example, as shown in
FIG. 7A, readout block size 70 decreases in pixels when the data
quality is low. Conversely, as shown in FIG. 7B, readout block size
70 increases when the environment is favorable.
[0046] Occasionally, image quality may not be as good as desired.
The present invention thus provides various approaches for
improving image quality. Three of these approaches are described in
FIGS. 8-10. Referring first to FIG. 8, as shown, the process is
started in step L1. In step L2, the reader sends out default setup
to the RFID transponder. Such setup can address variables such as
readout range, integration time, ADC setup, processing type,
channel and source, coding, etc. Regardless, in step L3, RFID
readout and transmission is made. In step L4, it is determined
whether sufficient quality exists. Sufficient quality can be
determined by comparing the image to a predetermined threshold.
This can be accomplished by the RFID reader using techniques such
as a threshold pixel scan, a gray scale pixel scan, and/or image
recognized data. If quality does not meet thresholds, the reader
can adjust the setup in step L5. Once quality is sufficient, the
process can end in step L6.
[0047] Referring to FIG. 9, another quality-improving technique
will be explained. As shown, the process is started in step M1. In
step M2, the reader sends out default setup to the RFID
transponder. As indicated above, such setup can address variables
such as readout range, integration time, ADC setup, processing
type, channel and source, coding, etc. Regardless, in step M3, RFID
readout and transmission is made. In step M4, it is determined
whether sufficient quality exists. Sufficient quality can be
determined by comparing the image to a predetermined threshold.
This can be accomplished by the RFID reader using techniques such
as a threshold pixel scan, a gray scale pixel scan, and/or image
recognized data. If quality does not meet thresholds, the reader
can deduce the readout range in step M5. Alternatively, along these
lines, if range is insufficient, any of the techniques of the
above-incorporated patent applications can be implemented. For
example, range can be extended using fields generated by other RFID
transponders, by deriving power from power lines, by deriving
additional power from wireless networks, etc.
[0048] Referring to FIG. 10, another quality-improving technique
will be explained. As shown, the process is started in step N1. In
step N2, the reader sends out default setup to the RFID
transponder. As indicated above, such setup can address variables
such as readout range, integration time, ADC setup, processing
type, channel and source, coding, etc. Regardless, in step N3, RFID
readout and transmission is made. In step N4, it is determined
whether sufficient quality exists. Sufficient quality can be
determined by comparing the image to a predetermined threshold.
This can be accomplished by the RFID reader using techniques such
as a threshold pixel scan, a gray scale pixel scan, and/or image
recognized data. If quality does not meet thresholds, the
integration time per pixel can be increased in step N5. Once
quality is sufficient, the process can end in step N6.
[0049] The foregoing description of various aspects of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed and, obviously, many
modifications and variations are possible. Such modifications and
variations that may be apparent to a person skilled in the art are
intended to be included within the scope of the invention as
defined by the accompanying claims.
* * * * *